This is NOT to be confused with the aquatic invasive European water chestnut (Trapa natans)!
Asian water chestnuts (Eleocharis dulcis) and European water chestnuts (Trapa natans) are two unrelated water plants that carry the same name.
The Asian water chestnut resembles a small muddy tulip bulb and is sweet and crunchy; the European water chestnut resembles a tiny horned bull’s head and is quite starchy.
Americans are most familiar with the Chinese water chestnut. Chinese water chestnuts grow underwater in mud, have brown or black scale-like leaves, and are round, though somewhat flattened. They are the roots of an aquatic plant that grows in freshwater ponds, marshes, lakes, and slow-moving rivers and streams in Japan, Taiwan, China, Thailand, and Australia. They are difficult to harvest, explaining their generally high price. Chinese water chestnuts have mildly sweet, crisp, white flesh and are excellent raw on skewers with dip/